JP2010116732A - Tunnel excavator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tunnel excavator capable of enhancing water cut-off performance. <P>SOLUTION: This tunnel excavator 1 includes a front barrel 2 having a rectangular cross section, a rear barrel 3 having a rectangular cross section, and a center-folding part 5 for connecting center-foldably the front barrel 2 and the rear barrel 3, and provided with a water cut-off seal 4 between the front barrel 2 and the rear barrel 3, and the center-folding part 5 is formed into a cylindrical shape or a compound cylindrical shape. The center-folding part 5 includes a recess 10 provided in a rear end part of the front barrel 2, and having an inner circumferential face formed into spherical shape, a protrusion 11 provided in a front end part of the rear barrel 3, and having an outer circumferential face formed to be fit to the inner circumferential face of the recess 10, and engaged with the recess 10, and the water cut-off seal 4 provided between the recess 10 and the protrusion 11. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a tunnel excavator in which a front cylinder having a rectangular cross section and a rear cylinder having a rectangular cross section are connected so as to be able to be folded.

  Circular shields are the mainstream in shield and propulsion methods, which are techniques for digging underground tunnels in urban areas, etc., but recently, irregular cross-sections such as rectangular cross-sections in all fields such as electric power, subways, common grooves, and sewer A tunnel is being used.

  As shown in FIGS. 3 (a), 3 (b), and 4, a tunnel excavator 31 that excavates a tunnel having a rectangular cross section is provided with a front cylinder 32 having a rectangular cross section and a rear cylinder 33 having a rectangular cross section. A middle fold portion 35 having a seal 34 is connected so as to be foldable. A circular main cutter 36 and a small-diameter corner cutter 37 are provided at the front portion of the front barrel 32 so as to surround the main cutter 36. Inside the middle folding portion 35, a middle folding device (a middle folding jack) 38 is provided as a direction control mechanism.

  In a conventional tunnel excavator for excavating a tunnel having such a rectangular cross section, when a folding device is provided as a direction control mechanism, the middle folding portion also has a rectangular cross section (see, for example, FIG. 3B) and is longitudinally cut. The surface was straight (for example, see FIG. 3A) or tapered.

  The prior art document information related to the invention of this application includes the following.

JP 2004-250889 A Japanese Patent No. 29996620

  However, in the tunnel excavator 31, when the middle folding angle of the middle folding portion 35 is increased beyond 1 to 2 °, the shape of the water seal 34 at the corner portion 35c of the middle folding portion 35 becomes complicated, and the middle folding portion 35 is bent. The change in the seal tightening time will increase. For this reason, in the tunnel excavator 31, it is difficult to follow the water stop seal 34 at the corner portion 35 c of the middle folded portion 35, and the water stop performance of the middle folded portion 35 is reduced.

  Therefore, an object of the present invention is to provide a tunnel excavator with improved water stopping performance.

  In order to achieve the above object, the present invention provides a front torso having a rectangular cross section, a rear torso having a rectangular cross section, and connecting the front torso and the rear to each other so that the front torso can be folded. A tunnel excavator provided with a middle fold portion provided with a water-stop seal between the trunk and the middle fold portion having a cylindrical shape or a composite cylindrical shape.

  The bent portion is provided at the rear end portion of the front cylinder and has an inner peripheral surface formed in a spherical shape, and is provided at the front end portion of the rear cylinder according to the shape of the inner peripheral surface of the recess. It is preferable that the outer peripheral surface is formed, and includes a convex portion that engages with the concave portion, and a water-stop seal provided between the concave portion and the convex portion.

  At least one of the rear end of the front cylinder and the front end of the rear cylinder may be provided with a jet outlet for ejecting a removal fluid for removing earth and sand that has entered between the front cylinder and the rear cylinder.

  According to the present invention, even in a tunnel excavator that excavates a tunnel having a rectangular cross section, the same folding seal performance as that of a tunnel excavator that excavates a tunnel having an ordinary circular cross section can be obtained.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings. FIG. 1A is a longitudinal sectional view of a tunnel excavator showing a preferred embodiment of the present invention, and FIG. 1B is a sectional view taken along line 1B-1B. FIG. 2 is a front view of FIG. 1A viewed from the 2A direction.

  As shown in FIGS. 1 (a), 1 (b), and 2, a tunnel excavator 1 according to the present embodiment is a main push type tunnel excavator, and has a cylindrical front trunk 2 having a rectangular cross section. And a cylindrical rear cylinder 3 having a rectangular cross section having substantially the same shape as that of the front cylinder 2, the front cylinder 2 and the rear cylinder 3 are connected so as to be able to be folded, and the front cylinder 2 and the rear cylinder 3 An intermediate folding part 5 provided with a water-stop seal 4 in between is provided, and the whole folding part 5 is formed into a cylindrical shape.

  The front cylinder 2 includes a square tube 2a, a partition wall 2b provided at the front portion of the square tube 2a and partitioning the inside of the square tube 2 back and forth, and a front lid 2c provided at the rear end of the square tube 2a. The rear barrel 3 includes a rectangular tube 3a and a rear lid 3c provided at the front end of the rectangular tube 3a.

  At the center of the front portion of the front barrel 2, a circular main cutter 6 for excavating natural ground by cutting the face by rotational driving is provided via a partition wall 2b. At the four corners of the front end portion of the front barrel 2, small-diameter corner cutters 7 for excavating the corner portions of the tunnel having a rectangular cross section so as to surround the main cutter 6 are provided via the partition walls 2b.

  A segment abutting portion for obtaining a thrust in the excavation direction at the rear end of the rear barrel 3 abuts on a cylindrical segment ring 8 having a rectangular cross section which is pushed by a main pushing jack installed on a starting stand. 9 is provided. The segment ring 8 is sequentially inserted at the starting edge of the start-up counter according to the excavation of the tunnel excavator 1. In the present embodiment, a steel segment ring 8 is used.

  The middle bent portion 5 is provided at the rear end portion of the front barrel 2 and has a spherical inner surface formed therein, and is provided at the front end portion of the rear barrel 3 and has the shape of the inner peripheral surface of the concave portion 10. In addition, an outer peripheral surface is formed, and includes a convex portion 11 that engages with the concave portion 10, and a water-stop seal (centered seal) 4 provided between the concave portion 10 and the convex portion 11.

  In this embodiment, the water seal 4 is provided on the inner peripheral surface of the recess 10, and the protrusion 11 is inserted so as to engage with the recess 10. The outer peripheral surface of the convex part 11 is a contact surface of the water-stop seal 4 and is formed in a shape that does not include a linear shape. In this embodiment, the outer peripheral surface of the convex part 11 was formed circularly along the circumferential direction. Speaking of the cross-sectional shape, the convex portion 11 has a vertical cross section formed in an R shape (arc shape) and a horizontal cross section formed in a circle.

  Inside the middle folding part 5, as a direction control mechanism, a middle folding device (a middle folding jack) 12 that connects the front trunk 2 and the rear trunk 3 and bends the front trunk 2 in an arbitrary direction by expansion and contraction, A plurality are provided at intervals in the circumferential direction.

  At the four corners of the front lid 2c, which is the rear end of the front cylinder 2, there are respectively provided outlets 13 for ejecting a removal fluid for removing earth and sand that have entered between the front cylinder 2 and the rear cylinder 3. A removal fluid supply means for pumping the removal fluid and supplying it to each jet port 13 is provided in the front barrel 2. Examples of the removal fluid include a lubricant that further increases the fluidity of the sediment after excavation, and compressed air.

  The operation of this embodiment will be described.

  The tunnel excavator 1 pushes the rear end surface of the rearmost segment ring 8 with a main push jack so that the segment abutting portion 9 of the rear trunk 3 is pushed by the front end surface of the foremost segment ring 8 and digs forward. I will do it. In the tunnel excavator 1, the front trunk 2 is bent by expansion and contraction of the middle folding device 12, thereby changing the digging direction to an arbitrary direction including not only the conventional vertical and horizontal directions but also an oblique direction.

  In the tunnel excavator 1, the whole bent portion 5 has a cylindrical shape. When the direction of excavation is changed, the bent portion 5 also bends in the same direction as the front trunk 2 having a rectangular cross section. A steep corner (corner) is not formed. For this reason, in the tunnel excavator 1, no matter which direction the excavation direction is changed, the change of the seal tightening allowance at the time of the middle break is constant, and with respect to the water stop seal 4 provided on the front trunk 2 having a rectangular cross section, The rear trunk 3 having a rectangular cross section follows well. That is, in the tunnel excavator 1, the followability of the water stop seal 4 is improved.

  As a result, according to the tunnel excavator 1, the water stopping performance of the folded portion 5 is improved. Therefore, even in a tunnel excavator that excavates a tunnel having a rectangular cross section, Equivalent middle-fold sealing performance is obtained.

  Further, the tunnel excavator 1 includes a concave portion 10 having an inner peripheral surface formed into a spherical shape, and a convex portion that has an outer peripheral surface formed in accordance with the shape of the inner peripheral surface of the concave portion 10 and that engages with the concave portion 10. 11 and the water stop seal 4 provided between the concave portion 10 and the convex portion 11 constitute a middle bent portion 5.

  For this reason, in the tunnel excavator 1, while maintaining the water stopping performance of the middle folding part 5, the convex part 11 engages with the concave part 10, and the middle folding part 5 moves smoothly, and the middle folding angle of the middle folding part 5 Can be increased.

  Furthermore, the tunnel excavator 1 ejects the removal fluid backward from the jet port 13 provided in the front lid 2c which is the rear end of the front barrel 2, so that the front barrel 2 is mainly used when the front barrel 2 is bent. Sediment that has entered between the rear barrel 3 and the rear trunk 3 can be removed, so that not only ordinary straight or curved excavation but also smooth excavation work can be performed even when the excavation direction changes frequently.

  In the above-described embodiment, an example in which the entire folded portion 5 is formed into a cylindrical shape has been described. However, even if the entire folded portion is a composite cylindrical shape in which a plurality of cylindrical pieces having different diameters are combined, the same as described above. Action and effect are obtained. This composite cylindrical shape includes an elliptic cylindrical shape and a shape in which both sides are semi-cylindrical and a plate-like shape is formed between the two sides, and a sharp corner portion is not formed at the middle bent portion other than the cylinder.

  Moreover, in the said embodiment, although the recessed part 10 was provided in the rear-end part of the front cylinder 2, and the convex part 11 engaged with the recessed part 10 was provided in the front-end part of the rear cylinder 3, conversely, the front-end part of a rear cylinder A concave portion may be provided on the rear, and a convex portion that engages with the concave portion may be provided at the rear end portion of the front barrel.

  Furthermore, in the said embodiment, although the jet nozzle 13 was provided in the rear-end surface of the front cylinder 2, in addition to this, a jet nozzle may be provided in the four corners of the rear cover 3c used as the front end of the rear cylinder 3, respectively. The jet port may be provided only on the rear barrel 3 side.

  In the above embodiment, the main push type tunnel excavator has been described, but the segment excavator 1 according to the present embodiment, for example, a segment assembling apparatus that constructs a tunnel by assembling segments in a tunnel excavated with a cutter, The present invention can also be applied to a rectangular shield machine equipped with a shield jack (propulsion jack) for propelling a reaction force on the tip of an existing segment of a tunnel.

FIG. 1A is a longitudinal sectional view of a tunnel excavator showing a preferred embodiment of the present invention, and FIG. 1B is a sectional view taken along line 1B-1B. It is the front view which looked at Drawing 1 (a) from the 2A direction. 3A is a longitudinal sectional view of a conventional tunnel excavator, and FIG. 3B is a sectional view taken along line 3B-3B. It is the front view which looked at Fig.3 (a) from the 4A direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tunnel excavator 2 Front trunk 3 Rear trunk 4 Water stop seal 5 Middle folding part

Claims (3)

  A front torso having a rectangular cross section, a rear torso having a rectangular cross section, and the front torso and the rear torso are connected to each other so as to be able to be folded, and a middle fold portion is provided with a waterproof seal between the front and rear torso A tunnel excavator characterized in that the bent portion has a cylindrical shape or a composite cylindrical shape.   The bent portion is provided at the rear end portion of the front cylinder and has an inner peripheral surface formed in a spherical shape, and is provided at the front end portion of the rear cylinder according to the shape of the inner peripheral surface of the recess. The tunnel excavator according to claim 1, further comprising: a convex portion engaging with the concave portion; and a water stop seal provided between the concave portion and the convex portion.   A jet nozzle for ejecting a removal fluid for removing earth and sand that has entered between the front cylinder and the rear cylinder is provided in at least one of a rear end of the front cylinder and a front end of the rear cylinder. The tunnel excavator according to 1 or 2.

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